I've read the Bible enough to know that if someone had killed one of King David's wives, David would have hunted them with a spear and impaled them to a wall. Then he would have written a Psalm about it. God would have blessed him the next spring with a bumper harvest. My point being-- these two losers should be fried. There's nothing wrong with getting angry about things- being passionate. People need to feel a little heat.
Forgiveness, at the Human level, is often a cathartic for the person doing the forgiving. Better to forgive and get on with your life than allow the bile of hate to eat at your soul. King David aside - if she were to hunt them down and kill them, God may or may not bless her, but she would pay a worse legal penalty than them. Kind of funny how so many who have probably never actually done any serious retribution/vengeance are so quick to exhort others to it. They also use the Bible to justify non-Christian thoughts/actions.
And this is why you do NOT get married (along with a myriad of other reasons). Too many women are shallow and fickle, and really have no more regard for their husband than the family pet. She’ll be married again within the year. No biggie.